Skip to content

thermocline and turnover

Featured Replies

I have a general knowledge of thermoclime i guess ..meaning i've seen it on my electronics in some of the deeper lakes i fish . but i really don't know how or when to adjust to it ...I hear about lakes turning over , but really don't understand it ..most of my lakes are shallow 6 to 10 ft ... Does every lake have  thermocline , even shallow ones ?

I really doubt that a 6-10 ft lake would have one.  Yes there will be a slight water temp difference but not huge temp difference.

Here are some real good articles that helped me out alot

http://www.bassresource.com/search/search.php

  • Super User

Thermocline and turnover are more common in deep lakes, like Gman said, a 10 ft lake.....I don 't think so. The catch is how to read the termocline, some say that it 's clearly visible in the finder, in my experience, never seen one; I know there 's a thermocline at a certain depth by seeing how the fish are distributed along the water column, if you see fish from the surface to the bottom then there 's no thermocline, if you see fish up to a certain depth and no fish from that depth to the bottom then there 's a thermocline and you can take as reference the depth at which you found the deepest fish on the screen. Then you can rule out anything that 's below that depth and fish from that depth up.

To see a thermocline with sonar requires going to manual sensitivity and running it to 100%. Look for a horizontal shaded band splitting the screen. It can show a foot thick or maybe 15 feet thick. I doubt you could read a screen in 6-10' of water on high sensitivity. You can check for a thermocline by just dipping the rod tip deep and hold it there a moment, then jerking it out and feeling for a cold tip. If you find colder water than what's on the surface, you might have a thermocline. Shallow lakes generally get good mixing of water to the bottom, and if there's vegetation on bottom fresh oxygen mixes up from bottom, and the water temperature is pretty consistent all the way down, no sudden changes. However, these days shallow lakes often heat up more than deep lakes, so dissolved oxygen can't stay in the water like it can in cooler water. That's why a river backwater full of vegetation might not hold bass now like it does in spring and fall.

Jim

Ironically I was thinking of posting about this topic later today.  Once again, Jim comes through with the answers I'm looking for.  Quick question though.  Are most decent fishfinders capeable of detecting thermoclines or does it have to be a $1500 Navy submarine sonar mounted to a bass boat?

Probably any head unit that you can turn up sensitivity and turn off Fish ID on will show a thermocline. I run a pair of $600 Lowrance 332Cs that show it very easily. I had a $200 Bottomline that did it, and a cheap Humminbird & Lowrance Eagle that worked.

Jim

Here are the settings a forum buddy of mine uses.  I believe he uses lowrance finders.

ASP              Off

Upper Limit     10

Lower Limit    deeper than I plan to fish

Scroll Speed   I can't tell the difference so I leave it alone

Ping Speed     100%

Surface Clarity  off

Sensitivit          varies some set it at 90% but you can black out with that much

And I set gray scale around 20

I just purchase a new 900 series Hummingbird and it will show thermocline real well

I found some information, probably way more than we need, but ought to answer most questions about thermoclines in freshwater. Oceanic topics are interesting, too.

http://www.bassresource.com/fishing/thermocline.html

http://www.lakeforktexas.com/Pages/therm.html

http://www.ourlake.org/html/thermocline.html

http://everything2.com/index.pl?node_id=866332 (Interesting ocean thermocline facts, explains why sonar picks it up)

Jim

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Unfortunately, your content contains terms that we do not allow. Please edit your content to remove the highlighted words below.
Reply to this topic...

Recently Browsing 0

  • No registered users viewing this page.

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.